Refactoring Rails Applications
Jonathan Weiss, 26.05.2009
Peritor GmbH

Who am I ?
Jonathan Weiss
• Consultant for Peritor GmbH in Berlin
• Specialized in Rails, Scaling, Deployment, and Code Review
• Webistrano - Rails deployment tool
• FreeBSD Rubygems and Ruby on Rails maintainer
http://www.peritor.com
http://blog.innerewut.de
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Refactoring
A Definition:
Refactoring is the process of changing internal structure without modifying
its external functional behavior or existing functionality with the goals of
readability, maintainability, performance, extensibility, and simplicity.
Wikipedia
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From
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To
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(To)
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How?
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Live Coding Experiment
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Principles
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MVC
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Model
Core business model
Domain logic
Reusable
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View
Dumb representation to the outside
Targeted at specific use case
Displays desired information
Different views of one model
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Controller
Conductor & connector
Brokers client requests to backend
Decide & delegate rather then labor
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DRY
Principles
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You Ain’t Gonna Need It
Ron Jeffries:
Always implement things when you actually need them, never when you
just foresee that you need them.
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Live Coding Experiment
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Redmine
• A load-balancer distributes the incoming requests
• Some load-balancers will deliver static requests themselves
• Several Rails instances handle all requests
• Number of concurrent requests equals number of Rails instances
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Redmine
• Multiple projects support
• Flexible role based access control
• Flexible issue tracking system
• Gantt chart and calendar
• News, documents & files management
• Feeds & email notifications
• Per project wiki
• Per project forums
• Time tracking
• SCM integration (SVN, CVS, Git, Mercurial, Bazaar and Darcs)
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Q&A
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Peritor GmbH
Teutonenstraße 16
14129 Berlin
Telefon: +49 (0)30 69 20 09 84 0
Telefax: +49 (0)30 69 20 09 84 9
Internet: www.peritor.com
E-Mail: kontakt@peritor.com
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